1. Field of the Invention
The present invention relates to establishing communicative connections in a down-hole environment. In particular, the invention relates to systems and methods for aligning two terminal ends of first and second cables down-hole such that a signal is transmissible between the two cables.
2. Description of the Related Art
Often instruments and tools are positioned at down-hole locations within hydrocarbon producing wells to detect well conditions and control the operation of the well. Communication systems are provided so that an operator at a surface location can receive information from down-hole sensors and issue commands to down-hole tools. Some communication systems operate by generating and detecting pressure fluctuations in a fluid column extending into a well. These systems are often slow and unreliable. Other communication systems employ metallic wire conductors to transmit data signals and electric power. These systems are often susceptible to EMI noise and damaging effects of moisture and temperature conditions in a well. In many instances, optical fibers offer significant advantages over both metallic conductors and fluid-based communication systems. Data transmission rates through optical fibers are relatively high and communications through optical fibers are not as influenced by environmental conditions. Accordingly, fiber optic cable is increasingly employed in down-hole applications.
The use of optical fibers, however, does present some difficulties. For instance, the small diameter of typical optic fibers makes precise alignment increasingly critical when establishing connections down-hole. The total diameter of a typical single-mode optical cable may be about 400μ (microns), while a glass core of the fiber, through which optic signals are transmitted, may have a diameter of only about 8μ. The typical manufacturing tolerances of the materials used for components in a down-hole environment may be larger than the diameter of a of a fiber optic core. Thus, many typical mechanical mating techniques used for establishing down-hole connections may prove ineffective for fiber optics.